According to one aspect, a rotor structure and method of assembling a rotor structure for rotating machinery include a first rotor portion assembled on a tie bolt in abutment with a stop surface and a fastener assembled on the tie bolt at a second axial location spaced from the first axial location to capture the first rotor portion on the tie bolt between the first and second axial locations. A second rotor portion is secured on the tie bolt in abutment with a second stop surface spaced from the first stop surface.